The Press understands some were bought out of people's freezers at private properties and after deals were made at pubs.

An anonymous source said a lot people in Kaikoura knew what was going on, but it was not "the average civilian's" job to do anything about it.

Under the Fisheries Act, catching and illegally selling crayfish is punishable by up to five years imprisonment and/or a $250,000 fine.

MPI seized 10 cars, five boats and a tractor in the execution of 32 search warrants and more than 40 people were caught.

Director of compliance Dean Baigent said there had been a "thriving" black market in Kaikoura for some time.

Recreational black-marketers were selling whole cooked rock crayfish for between $10 and $15 each, he said.

CRAMAC5 spokesman Larnce Wichman said he was relieved no commercial operators, iwi members or charter operator had been implicated.

Wichman, who is also chairman of coastal guardian group Te Korowai o Te Tai o Marokura, said the arrests were "divisive" in the Kaikoura community, however, opinions were "weighed definitely against [black market activity] rather than for".

"It is going to be interesting to get the names out. They have been operating for some time - below the radar. The sad thing is there appears to be more problems when there is an abundant fishery," he said.

"[Poachers] can get it so easily and so quickly, but how long can a fishery or resource sustain that? This type of behaviour cannot be tolerated."

Te Korowai o Te Tai o Marokura secretary Gina Solomon, of Ngai Tahu and Ngati Kuri descent, said seafood black-marketing had been going on for several years, which was one of the reasons the coastal guardian group was set up.

"I do not know who the people are, [but] it is disappointing that this has been going on," she said.

Kevin William Clarke's dinghy and truck were confiscated in 2013 following a conviction in the Kaikoura District Court for illegal seafood sales. Judge Emma Smith said even though the Kaikoura man never took more than his daily limit, it was evident from inquiries made by fisheries officers that he was acquiring kina and crayfish for sale. Judge Smith said police found 43 individually wrapped crayfish in a freezer at Clarke's property and he exchanged texts with people placing orders.

In 2012, Christchurch plumber Mark Allan Webster admitted selling black-market crayfish that he caught near Kaikoura. According to a summary of facts in the Christchurch District Court, Webster did not hold any permits authorising him to take, sell or purchase crayfish commercially. Judge Jackie Moran fined him $2400 and ordered the forfeiture of his boat, freezer, boiler and crayfish pots - as well as the crayfish in his freezer.

Kaikoura restaurant manager Hamish David Malyon King was convicted and fined in the Kaikoura District Court in 2010 after topping one of the Black Rabbit Pizza Company's pizzas with crayfish from the wrong source. Fisheries officers inspected the Beach Rd restaurant and found 2.6 kilograms of crayfish meat, worth $450, but no receipts. In court, King admitted the crayfish had been caught recreationally and given to him. He and the company were fined a total $4000.